Recent development in ESWL (Extracorporeal Shock Wave Lithotripsy) for the treatment of kidney stones have been shown to be quite effective. This has raised the potential use of this modality for the treatment of common bile duct stones. Initial studies performed in Germany have shown this treatment to be safe and effective with minimal risk. The purpose of this study is to further evaluate this treatment modality and to assess its potential role for the treatment of common bile duct stones.